Rotary fluid-flow machines



Feb 14, 1957 T. D. H. ANDREWS ETAL 3,303,993

ROTARY FLUID-FLOW MACHINES Filed NOV. 12, 1964 Hill Imvaru-roes THO/7A5D. AIYDAEWS By PETEA SPEIYCE TQENEY United States Patent 3,303,993ROTARY FLUID-FLOW MACHINES Thomas D. H. Andrews and Peter Spence,Cheltenham, England, assignors to Dowty Technical Developments Limited,Brockhampton, England, a British company Filed Nov. 12, 1964, Ser. No.410,461

Claims priority, application Great Britain, Nov. 19, 1963,

3 Claims. (Cl. 230116) This invention relates to rotary fluid-flowmachines.

According to this invention, a rotary fluid-flow machine includes aturbine and compressor, the rotors of which are integrally formed as asingle rotatable member, having two separate sets of flow-definingvanes, or the like, the first set being turbine vanes tand the secondset being compressor vanes, the casing of the machine in which themember is rotatable being so shaped as to provide an entry to the firstset of vanes and also to provide a further entry to the second set ofvanes, and the casing being shaped also to provide channels in registrywith the exits of both sets of vanes such that the fluids discharged bythe compressor and the turbine are mixed together before discharge fromthe machine through a mixed fluid outlet.

The rotatable member may be of centrifugal type and the casing of scrollor annular type, the latter having a central entry to the compressor.The inlet to the turbine and the mixed fluid outlet may be each spacedapart on opposite sides of the central entry.

The fluid compressed by the compressor may be air, While the fluiddriving the turbine may be exhaust gases derived from the exhaustmanifold of an associated internal combustion engine.

The fluid flow through the compressor may be generallyradially-outwardly, while the fluid flow through the turbine may begenerally radially inwardly.

It may be so arranged that the delivery from the compressor passesaround the outside of an inner portion of the casing through which theexhaust gases leaving the turbine rotor pass, so that an insulating airenvelope is provided around that portion of the casing.

One embodiment of the invention will now be particularly described byway of example with reference to the accompanying drawing which shows incross-section a rotary fluid-flow machine in the form of aturbine-compressor unit.

Referring to the drawing, the turbine-compressor unit comprises ascroll-type casing 11 formed in two parts 12 and 13. The part 13 of thecasing is extended to the right in the drawing to form a sump 14 and tohouse ball bearings 15 and 16 for rotatably supporting a shaft 17 whichprojects to the left in the drawing into the part 12 of the casing.

The part 12 of the casing has a central entry 18 to the eye of a singlerotatable member 19 mounted upon the left-hand end portion of the shaft17.

The single rotatable member 19 constitutes an integral compressor andturbine rotor of centrifugal type having an inner set of vanes 20 whichare the compressor vanes which register with the central entry 18, andhaving also an outer set of vanes 21, which are the turbine vanes, andwhich register on their inlet side with a ring of stator blades 22.

The casing 12 is provided with an inlet 23 through which exhaust gasesfrom the exhaust manifold of an associated internal combustion engine(not shown), can pass into the turbine section of the turbine-compressorunit.

The parts 12 and 13 of the casing 11, together form an outer annularcasing, but within it there is provided an inner annular casing 24, theinlet 23 being connected to the interior of the casing 24 by connectingmeans 25.

The part 12 of the casing 11 is also provided with a mixed gas outlet26, both the exhaust inlet 23 and the outlet 26 being spaced apart onopposite sides of the central entry 18.

The outlet side of the compressor portion 20 of the single rotatablemember 19 opens into an envelope chamber 27 formed between the innerannular casing 24 and the adjacent wall of the part 13 of the casing 11.

A labyrinth seal 28 is provided to the left of the ball bearing 15between the shaft .17 and an insert 29 secured to the part 13 of thecasing 11. The insert 29 carries a ring of substantially radial statorblades 29a which are positioned on the outlet side of the compressor. Afurther labyrinth seal 30 is provided between the rotatable member 19and the part 12 of the casing 11, this seal surrounding the centralinlet 18. Another labyrinth seal 31, for gas sealing, is provided in theregion between the stator blades 22 and 29a.

In operation of the turbine-compressor unit, exhaust gases from theassociated internal combustion engine pass through the exhaust inlet 23and the connecting means 25 into the interior of the casing 24. Thegases then pass through the stator blades 22 and through the vanes 21 ofthe turbine portion of the rotatable member 19, the resultant expansionthrough the turbine effecting rotation of this member. The exhaust gasesdischarging from the turbine pass through the annular chamber 32 formedbetween the casing 24 and the wall of the casing parts 12 and 13.

With rotation of the rotatable member 19 the compressor portion, formedby the vanes 20, draws in air from the surrounding atmosphere throughthe central inlet 18, compressing this air and discharging itradiallyoutwardly through the stator blades 29a into the envelopechamber 27. This air, in so passing around the outside of the casing 24,has an insulating effect between the easing 24 and the outer casingcomponents before passing into the chamber 32. The arrangement is suchthat the exhaust gases discharging from the turbine and the compressedair delivered by the compressor through the envelope chamber 27 mixtogether efliciently in the annular chamber 32 before passing from theunit through the mixed outlet 26.

The casing parts 12 and 13 are connectible together in a number ofrelative rotational positions to afford adjustment of the positioning ofthe inlet 23 and the outlet 26 in relation to the sump 14.

Further, conventional waste-gate means (not shown) may be incorporatedin the turbine-compressor unit in conjunction with the connecting means25 to permit some of the exhaust gases to by-pass the turbine when sonecessary.

Such a turbine-compressor unit may with advantage be employed in theexhaust system of an internal combustion engine for introducingadditional air into the exhaust gases upstream of a device for reducingthe toxic element content of the exhaust gases passing to atmosphere.

Alternatively, the turbine-compressor unit may be utilised for desiredand eflicient mixing of any two fluids, where one of the fluids can besupplied under pressure so as to provide the driving energy for theturbine section of the unit.

By providing the turbine and compressor rotors in the form of a singlerotatable member, considerable simplicity in the design of the casing inwhich the member is rotatably mounted, is achieved.

Although in the embodiment described the com-pressor in generally of theradial-outward flow type and the turbine gene-rally of theradial-inward-flow type, in alternative embodiments of the invention, bysuitable modification of the rotor and easing, other flow directions forboth turbine and compressor fluid canbe accommodated.

We claim as our invention:

1. A rotary fluid-flow machine including a turbine and compressor, therotors of which are integrally formed 'as a single rotatable member ofwholly centrifugal type having two separate sets of flow-defining vanes,the first set being turbine vanes and the second set being compressorvanes, the casing of the machine in which the member is rotatable beingso shaped as to provide an entry to the first set of vanes and also toprovide a further entry to the second set of vances, and the casingbeing shaped also to provide two separate channels respectively inregistry with the exits of the sets of vanes, said separate channels soopening into each other that the fluids discharged by the compressor andthe turbine are mixed together downstream of the turbine vanes butbefore discharge from the machine through a mixed fluid outlet, the saidcasing having an inner portion through the interior of which the exhaustgases leaving the turbine pass, and around the outside of which thefluid delivered by the compressor passes, so that an insulating airenvelope is provided around that portion of the casing.

2. A rotary fluid-flow machine as claimed in claim 1,

forms a sump for the machine and houses bearings for supporting thesingle rotatable member, while the other part includes the entries andthe outlet of the machine.

3. A rotary fluid-flow machine as claimed in claim 1, wherein the casingparts are connectible together in a number of relative rotationalpositions to afiord adjustment of the positioning of the inlet to theturbine and of the mixed fluid outlet in relation to the sump.

References Cited by the Examiner UNITED STATES PATENTS 1,181,780 5/1916Loewenstein 230-116 1,368,751 2/1921 Rateau 230-116 2,238,502 4/1941Muir et al.

2,516,822 7/1950 Yates 10387 2,611,241 9/1952 Schulz.

2,873,945 2/1959 Kuhn 230116 FOREIGN PATENTS 148,822 12/1921 GreatBritain.

342,409 7/1936 Italy.

ROBERT M. WALKER, Primary Examiner.

1. A ROTARY FLUID-FLOW MACHINE INCLUDING A TURBINE AND COMPRESSOR, THEROTORS OF WHICH ARE INTEGRALLY FORMED AS A SINGLE ROTATABLE MEMBER OFWHOLLY CENTRIFUGAL TYYPE HAVING TWO SEPARATE SETS OF FLOW-DEFININGVANES, THE FIRST SET BEING TURBINE VANES AND THE SECOND SET BEINGCOMPRESSOR VANES, THE CASING OF THE MACHINE IN WHICH THE MEMBER ISROTATABLE BEING SO SHAPED AS TO PROVIDE AN ENTRY TO THE FIRST SET OFVANES AND ALSO TO PROVIDE A FURTHER ENTRY TO THE SECOND SET OF VANCES,AND THE CASING BEING SHAPED ALSO TO PROVIDE TWO SEPARATE CHANNELSRESPECTIVELY IN REGISTRY WITH THE EXITS OF THE SETS OF VANES, SAIDSEPARATE CHANNELS SO OPENING INTO EACH OTHER THAT THE FLUIDS DISCHARGEDBY THE COMPRESSOR AND THE TURBINE ARE MIXED TOGETHER DOWNSTREAM OF THETURBINE VANES BUT BEFORE DISCHARGE FROM THE MACHINE THROUGH A MIXEDFLUID OUTLET, THE SAID CASING HAVING AN INNER PORTION THROUGH THEINTERIOR OF WHICH THE EXHAUST GASES LEAVING THE TURBINE PASS, AND AROUNDTHE OUTSIDE OF WHICH THE FLUID DELIVERED BY THE COMPRESSOR PASSES, SOTHAT AN INSULATING AIR ENVELOPE IS PROVIDED AROUND THAT PORTION OF THECASING.